Elevator-door-operating mechanism



Sept. is, 1928. 1,684,433

W. B. CROWELL ELEVATOR DOOR OPERATING MECHANISM Filed June 21, 1923 2 Sheets-Sheet 1 IN V EN TOR M Md hm 1 ATTORNEY Patented Sept. 18, 1928.

UNTE STATES WILLIAM B. CROWELL, OF NEW YORK, N. Y.

ELEVATOR-DOOR-OPERATING IVIECHANISM.

Application filed June 21,

The present invention relates to a dooroperating mechanism, and more particularly to a fluid pressure actuated device in which cushioning action is attained in the movements of the mechanism by means of a portion of the operating pressure fluid.

In the operation of elevator doors, one of the first requisites is safety in operation, and in order to attain such safety elevator doors are generally manually operated. Such manual operation results in a loss of operating speed and also places an. unnecessary burden upon the elevator operators. Because of the heavy work in connection with the handling of elevator doors, it is the common practice to employ men for such operation, although it would be preferable in many cases to employ women for this type of work. lVith power operation of the elevator doors it becomes practical to employ women for the general elevator operation. Various devices have heretofore been suggested for power operation of elevator doors so as to overcome the heavy manual operation, but none of the devices have proved entirely satisfactory as far as I am aware.

Among the objects of the present invention are:

To provide a means for operating elevator doors and other mechanisms in which any desired speed of operation may be attained.

To provide a means for operating elevator doors and other mechanisms in which the operation of the mechanism takes place with yieldahle force so that in case of an object bstructing the movement oi. the mechanism, the mechanism may be halted without the application of an unduly great force.

To provide cushioning means in a. poweroperated mechanism in which the operating fluid ma be employed to attain cushioning or checking action and thus avoid the use of extraneous liquids or fluids.

To provide a power-actuated means for operating elevator doors and other mechanisms which is simple in operation and which may he ada 'uted to be installed with the form of ci tor door-operating mechanism now gen- ..llv employed.

\Vitn these and other objects in View, the in vention comprises the various features hereinafter described and more particularly defined the claims.

T Jar-ions features of the invention will 1923. Serial No. 646,780.

be described in connect-ion with the accompanying drawings, in which Fig. 1 is a view of the device as applied "for actuating elevator doors;

Fig. 2 is a sectional view in elevation of the preferred form of the invention;

Fig. 3 is a fragmentary sectional view taken on the line 33 of Fig. 2 showing the control valve in position for admission of pressure fluid to the operating cylinder;

Fig. 4 is a fragmentary sectional view of the lower portion of the operating cylinder showing the control valve thereof in exhaust position, and

Fig. 5 is a sectional View through the exhaust chamber, exhaust pipe and control valve of the cylinder showing the position of the main exhaust port in the valve when the valve is'in the position shown in Fig. 1 for admission of fluid pressure.

The present invention is particularly adapted for the operation of elevator door mechanisms, although it is to be understood that the device may be employed and adapted for the operation of other mechanisms, such, for example, as signal devices in which a rapid action together with cushioning in the movements of the mechanism is required. For the purpose of illustrating the preferred mode of application of the invention, a device embodying the features thereof is shown in Fig. 1 in operative position as applied to the toggle levers of an elevator door.

The numeral 1 designates the operating device which is pivotally supported at one end upon a bracket 2 attached to an elevator hatchwa-y, and is connected through its piston rod to a lug 3 on a link 4 of a toggle lever 5. The toggle lever 5 is pivotally attached at one end to a bracket 6 on the elevator hatchway and is pivotally connected at its other end to an elevator door 7, as shown in the drawings. The elevator door is supported in the usual manner on rollers adapted to move on an overhead track 8. In order that the door may be manually operated in case of failure of power, a handle 9 is provided which is connected to the toggle levers in the usual manner. Should the door be manually operated, without applying compressed airorother operating fluid to the power mechanism. the device will operate merely as a door check and provide cushioning or checking action in the opening and closin movements of door. A switch it) operatively attached the toggle lever 5 is connected in the elevator operating circuit, and serves to break the controller circuit when the elevator door is opened.

The preferred form of the invention comprises a cylinder casing 12 having upper head 14 and a lower head 16 which are at tached to the cylinder preferably by means of screw-thread connections 18 and 20. In the cylinder is a piston 22 having a piston rod 24 connected thereto, the piston rod being adapted to pass upwardly tl rough an opening 25 in the upper head 14 of the cylinder. The piston 22 may be of any suitable form. but I prefer the use of a hollow cup piston of the form shown in the drawing having a flange 28 which is adapted for holding a spring- 30 which surrounds the piston rod 24 and is held in place at its upper end by means of a partition 31 in the cylinder. This spring 30 is compressed as the piston 22 moves upwardly in the opening movement of the door. The resulting compression of the spring 30 stores energy in the spring, and this one gy thus stored is sufficient to cause a return movement of the piston 22 to its lowermost position when atmospheric pressure prevails below the piston. Attached to the face of the piston 22 is a leather washer 26 by means of which a smooth sliding action between the piston and cylinder is attained and which serves also to prevent leakage of pressure fluid between the piston and cylinder walls.

The piston 22 may be actuated in its forward movement by means of pressure fluid which is admitted below the piston through a port 43 in the cylinder head 16. Attached to the cylinder head 16 and preferably integral therewith is a valve casing 41 within which is a valve to control admission of operating fluid to the cylinder. Connected to the valve casing 41 is a nipple 38 to which an operating fluid conducting pipe may be attached. A passageway or port 42 in the valve 40 serves to conduct fluid to the port 43 when the valve is turned so as to permit passage of fluid. The operation of the valve may be controlled by means such, for example, as a manually operated lever having: stops whereby the lever may be readily placed in position for admission or cut-off. In addition to controlling admission and cut-off of the operating fluid, the valve may also be employed for controlling the exhaust of operating fluid from the operating cylinder in a manner to be more fully described.

In order to attain cushioning action for the forward stroke of the piston, I provide means for by-passing a partof the pressure fluid after a predetermined movement of the piston in the cylinder and utilizing the bypassed fluid for opposing the forward movement of the piston. For the purpose of bypassing fluid, I provide a chamber 44, prefer ably attached to a cylinder near the lower end thereof above the valve casing 41. The

external chamber 44 communicates with the id cylinder casing 12 through a port 46, with the upper end of the cylinder casing means or" a pipe or conduit 48 through a port 49 in the upper head 14. -eittuchcd to the piston rod 24 in the end of the cylinder to which fluid is by-passed, is a se ond piston 34, which may be of any fern adapted to slide in the cylinder and provide cushioning action by means of the fluid liietween the piston and cylinder head. I preferably employ a piston of the cup plunger type and provide a stationary plunger 36 attached to the cyl inder head 14, which will pass into or be en veloped by the cup piston in its upward stroke. The cup plunger is adapted to seat on the partition 31 when the piston 22 is in its lowermost position in the cylinder. A leather cup washer is provided at the top of cup plunger 34 to prevent leakage of pressure fluid between the plunger and cylinderwalls and also to provide a smooth sliding contact between the inner walls of the cup plunger and the plunger 36 attached to the cylinder head. By means of the conduit 48 pressure fluid is passed from the portion the cylinder below the piston, after movement thereof to uncover the port 46, to the chamber between the cup plunger and the cylinder head 14, and provides cushioning action for the forward stroke of the piston. The passage of fluid through the conduit 48 is regulated by means of a regulating throttle valve or reducing valve 54 by means of which any desired pressure drop may beattained from the piston end of the cylinder to the plunger end thereof. In order to permit passage of fluid only in one direction through the conduit, I provide a cheer; valve of any suitable form such, for example, as a ball valve shown in Fig. 2 of the drawings, com p -ising a ball held in place in the conduit by means of a coupling sleeve 52.

In order to provide for exhaust of pr' fluid from. the piston end of the cylinder dr iirg the return stroke of the piston from its uppermost position to the point at which th port 46 is again covered, an exhaust pipe 56 is connected to the chamber 44. Any suitable means of control through the exhaust pipe 56 may be provided, but I preferably connect the pipe with the valve casing 41 so that ere.

hau-st and admission may be controlled by the same valve. In the valve 40 I provide a port 57, and in the valve casing 41 I provide corresponding port 58 so that when the valve is in exhaust position there will be a free passage through the ports from the chamber 44 to the atmosphere. During the return movement of the piston from the port 46 to the lower end of the cylinder. communication with chamber 44 is cut elf. and the residual pressure fluid in the cylinder is gradualtil newness ly exhausted therefrom through the port and a passage 59 which communicates with passage 4-2 which in the exhaust position turned so as to communicate with an exhaust opening 63 in the 'alye casing, shown in Fig. 4 of the d airings. The residual fluid in the cylinder is thereby (2011'11)1'(?.- Q\'l and a. cushioning ot' the piston is therrhy attainml A regulating" screw 62 is secured in the exhaust opening 63 in the valve casing ll l y means of which the exit ot operati tlrid may he controlled and hy which any orsir-"d cushioning pressure Within cert ii 'iit may he attained during the return iuoYt of the piston to the piston end o the The operation oi the derire is Conuiressed air orother ])l't 11H is passed through the nipple throitnh a port 42 in the valve and is adm tted to ihe lower end ot the cylinder helou' the illrl therein. A pressure of :l'roui 35 to Tl) s may he used. which in the operedion o. yator doors will giy" a sutisla-tory spre: operation. and will he more rapid than we normally he ohtaiued hy manual opera By the admission of pressure lluiil the p a 22 is moved upvardly against the force ott :e opposing spring 30. and the cup plunger cushioning piston 34 in the upper part o i' the cylinder moves upwardly. can i initial slight compression of the air or p' sure medium in the chamber l etn'een the ri L plunger and the cylinder head ll. After the piston 22 has nioyed upwardly in the cylinder to a point Where the port 46 uncovered. pressure fluid passes through the port t; rod upwardly througz'h t pipe thr ugh the ilC at). regulating Valve 59 past the hall rhrekfl') and into the plunger end of the eylind through port 49 in the cylinder head ll. liy the time the port 1 51 unroyered h: in

ton the rup plunger lnS inoreo around the plunger 36 so that only .i of the upper part ot the eup plunge rarr ing the leather Washer 31' is suhierted to fluid pressure. As the piston mores upwardly heyond the port 46. more and more prep sure tluid passes into the plunger vol of th cylinder causing increase of prrwu'e on the cup plunger and wnsequently a greater eushioninyr action until the end l' he s. ohe is reached. lly holding the \alve ill in o tion for admi Ion the piston is rela z ill! its upper position and the door mechanism r: therehy maintained in open r rsztiou. Qhet:

it is desired to close the door. :1

inlet port. 43. and the passage communicatin; therewith registers with the port (323, eont rolled by regulating screw (32. The result-- in pressure drop helow the piston })t1 nuts the spring 30. aided hy the fluid under sure remaining in the upper portion of the cylinder aho e the plunger 34, to return the piston to its lowermost position. Durin; this return niorenzent ol the piston 22 in the cylinder. the pressure Fluid is at first exhausted through iort l6. chaniher ll. pipe it a pa: s f I)? in he Yalre il and into the atmosphere throng-go the exhaust port 59 in the Valve "fusing. soon as the piston 22 moves l'y the port it) in it return stroke. further exhaust through the main exhaust asszrg'eway is prevented. the pressure li\l is entrap 'ied in the lower or piston end the eylindei: l'illlllltf a eushioning action 1 the returi stroke. A gradual exhaust e ure fluid from the lower end ol' the ylnuler permitted. h m'eyer. through the i atine s-rren' ($21 by means oi Wliicli the -ed ot artion oi' the piston at the end oi' stroke. or the amount of cushioning action. may lie c nt illed. The linal exhaust. ot' pr ssure fluid takes place through the port i pass \e 59. passage 42 and into the annospnere ih rgh the regulating screw.

While the form of the invention whiea has heen deserihd constitutes the preferred form thereof. it to he understood that various changes or niodilirations may he made in the apparatus Without departing from the spirit or scope of the invention. In place ol the cup plunger and plunger to attain cushioning; action in the forward stroke of the piston. t'or ,X&l1lplC, li n'iight enipioy an ordinary pi ton to attain the sinie re ult hy entinppin air at. the end ot the cylinder. in plare ot the ehaniher 44, to eonncit the port ll; with the main exhaust port and with the upper eno ol the cylinder. l inigrht employ separate ron duits for this purpose. and in place of a siugrle valve for controlling admission and exhaust, I might employ sepa rate independent Valves, or valves whirl: are ttilllli 'ttll so as to he inter-dependent in thei ruoyeuwnts.

Having: thus deserihed the intention. what is elainied as new is:

1.111 a device ol' the i'lilrr; lesrrihed. a cylinder, a piston therein. nieans tor operati\ ely connecting! one ot' said parts to a llltt'llllnisni to he operated. means to! admitting pressure fluid to operate said pi ton in one direction. spring" means 'l or oppo. is: the said tluid pressure and tor returning the piston when the said tluid pressure releasetha rep and plunger in the rylinder for H hiouiug the movements of said piston. a on it renneeted to the lower portion ol' the cylinder and adapted to conduct tluid to the cup and plunger to produce ii'ushioninej artiou during: the pressure fluid operated stroke ot the pisthe piston, and means tor entrapping a portion of the operating fluid to attain cushioning action during the return stroke of the piston.

Q. In a device of the class described, a cylinder, a piston in the cylinder, means for connecting one of said parts to a mechanism to he operated, means tor admitting pre "are fluid to said cylinder on one side oi said pis ton for the purpose of moving .-aid piston in one direct on, means tor h npassinc' to the opposite s de ol' po -tion ot s-ai4l pressure thud alie- "l'iitilttt rnove ment of the said pi ton to custin?- tllti mow in; a portion of said pit "uid admission of pressure t'uu .e

side of said piston has l ce-n cut oh,

tcmporarilv retry said l)lQl\:l-.l(3 tiuid the return movement oft i for exhausting the sain I-iiilttlfi the tlnid from the c vl nt cr at l the end of the return movement 0 sai i ton, wherehy oscillatin zj tltl'iillli'lel of the said mechanism prevented.

3. In a device otthe ('l I dcscrihed, a cylinder, a piston, means tor conneciii'ie; one of ti said parts to a mechanis i to to operate means for admitting pre,-;snre 1" 2 side of the p ston. a spring; tor opposing the novement of said piston, means for in p inc a portion ot said tluid after a predetermined movement of the said pif-ton to cushion the movement thereof, an exhaust passage, tor exhausting; piston-operatin; nuid, and means t'or graduallv exhausting: the last portion of tluid from the cylinder to attain cushinning action of the piston on the return stroke thereot'.

in a device of the class d scrihe l. a cylinder, a piston in the cylinder, means for connet-tine? one of the part, so a mechanism to be operated, means t'or adi'nitting pressure tluid to said cylinder on one side of said pistru, a spring for opposing movement of the piston hv tluid pressure. a cup and plunger in the cvlinder to provide cushioning: action tor said piston, a conduit connecting the plunder end ol the c linder with a port in the cylindcr at a point interuied' to the ends thcreot wherehv pres fluid vrill he ad tilt d to the plunger end 0? the cvlinder when in the movement otthe piston the said port is placed in conin'uinication with the operatin pres-- sure tiuid. an exhaust eorniluit connecting; the said port, a valve in sa d condu t lltiYlIll' a port therein through which the pressure tluiil mav be exhausted trom the exhaust conduit, the said valve havinga second port which is restricted serving to e'r duallv exhaust, pressure fluid from the pi te-n ndot the mid cvlinder after the said pi ton has pane-l the d port in its return moveui 5. In a device of the class described, a cylinder, a piston in the cylinder, means for oper:v tively connecting one of the parts to a mechanism to be operated, means for admitting pressure fluid to one side of the piston, a spring for opposing the said fluid pressure and [or returning said piston when the tluid pressure is released, a plunger in the cylinder at one end thereot, a cup operative y connected to the piston and adapted to CUOPOi'tIiO with said plunger to cu.--hion the. movement of the piston in the direction ol' the plunger, an external chamber communicating with the cylinder intermediate its ends, a conduit connecting; said chamber with the cylinder at the plunger end thereot an exhaust conduit 7 llOlIl said clnunher, means to control the exhaust trom said conduit, and means tor :iuiu pressure is released, a plunger in the nder at one end thereof, a cup operatively ronucct d to the piston and adapted to cooperate with said plunger to cushion the movement of the piston in the direction of the plunger, an external chainher con'nminicating with the cylinder intermediate its ends, a con duit connecting said chamber with the cylin- LiLI at the plunger end thereof, a check valve in on id conduit, and means in said conduit for tfllltlt'lilg the pressure of fluid passing: therethrough, an exhaust conduit from said chamhcr, means to control the )(haust from said conduit, and means for cushioning the return stroke of the piston.

7. In a device of the class described, a cylinder, :1 piston in the cylinder, means operatively connecting one of the parts to a mechanism to be operated, a "alve controlling admission of fluid pressure to said cylinder to operate the piston in one direction, a coil spring tor operatingsaid piston the opposite direction, a second piston in said cylinder for cushioning the m-l'ivcnient ot the first named piston, a chzunher externa to said cylinder. a port in said cylinder con]- municnting; with sa d external chzunhcr, conduit between said external clian'ihe' and said cylinder at a point between sa d second piston and the adj cent cylinder flltl and adapted upon movement o the first mentioned piston a predetermined distance, to esahlish communi 'ation between opposite ends of the cylinder to provide cushioning fluid for said second mentioned piston. an exhaust conduit connected with said external chainher, an exhaust valve in said conduit depend ent in operation on said adu'iission valve,

lil

means for trapping a portion of fluid on the return stroke of the piston, and means for controlla'tily exhausting said entrapped fluid to attain cushioning action of the piston.

8. In a device 0 t the class described, a cylinder. a piston in the cylinder, means operatively connecting one of the parts to a mechanism to be operated, means. for admitting pressure fluid to said cylinder to operate the piston. a coil spring for moving said piston in the direction opposite to thatin which it is moved by fluid pressure, a cushioning piston adjacent one head of the cylinder and providing a chamber hctwcen said piston and head. a chamber external to said cylinder, a. port in said cylinder communicating with said extcrnal chamber. a conduit between said external chamber and the chamber between the cushioning piston and head adapted to conduct pressure fluid to the latter chamber when the piston uncovers said port. an exhaust conduit connected to said external chamber, an exhaust valve in said exhaust conduit. and means for providing cushioning action on the return stroke of the piston.

9. In a device of the class described, a cjlindcr, a piston in the cylinder, means operativciy ranrnecting one of the parts to a mecha nism to operated. a conduit for admitting picssure lluid connected to said cylinder for moving said piston in one direction, mechanical means tor moving said piston in the opposite direction, cushioning means at one end of the cylinder. a chamber external to said cylinder, a port in said cylinder intermediate the ends thereof con'nnunicating with said external chamber. a conduit between said externai chamber and said cushioning means for conducting pressure fluid thereto when the piston uncovers said port, an exhaust conduit i'rom said chamber operating on the return movement of the piston when said port is uncovered thereby, an exhaust conduit from the adm ssion end of the cylinder, and means in said conduit tor trappingfluid after the piston covers said port on return movement oi the piston.

10. In a device of the class described. a. cylinder, a piston in the cylinder. means operativcly connecting one of the parts to :1 mechanism to be operated. a c nduit for admitting pressure fluid connected to said cylinder for moving said piston in one direction, mechanical means for moving said piston in the opposite direction. cushioning means atone end 01* the cylinder, aport in said cylinder intermediate the ends thereof, a conduit from said port to said cushioning means, an exhaust conduit from said cylinder communicating with said port. an exhaust conduit from the admission end of the cylinder. means for regulating the exhaust through the latter conduit. and a valve controlling the admission and exhaust conduits.

11. In a device oi the class described. a

, cylinder, a piston in the cylinder. means for connecting one of the parts toa mechanism to be operated, means for adnntting pressure fluid to said cylinder on one side of said piston, mechanical means for movin said for retaining said cushioning fluid to assist in the return movement of said piston, means for cushioning the return movement ol said piston, and means whereby cushioning fluid is expelled at substantially the end of the return stroke oi' the piston.

.12. In a device of the class described. a cylinder, a piston in the cylinder, means operatively connecting one of the parts to mechanism to be operated. a second piston in said cylinder opcralivcly connected to the tirst piston and providing an end chamber in said cylinder between said second piston and the adjacent cylinder head. a port in said cylinder external tl rein to said end cham her, a conduit from said port to saidendchamher, means for 'egulating the passage of fluid through said conduit, an exhaust conduit connected to said port, a second exhaust conduit connected to the cylinder at the first piston end thereof, a valve controlling adi'nission of pressure fluid to said cylinder to move said lirsr mentioned piston in one direction and exhaust through said second exhaust conduit a coil spring for moving said piston in the opposite direction, and pressure regulating means connected to said second exhaust conduit to control cushioning action of said piston.

13. A door operating mechanism having in combination a piston, a cylinder in which the piston operates. operating connections between a door and said piston. means for storing energy during the operation oi' the piston in one direction comprising a single coiled spring and a chamber in said cylinder above said piston. and means tor conveying fluid under pressure to said chamber as said piston moves in the d rection to open the door. the pressure fluid thus stored in said chamber above said piston serving to assist, said single coiled spring in a tuating said piston on the return stroke.

1-1-. A. door operating nitwhanism having in combination a piston. a cvlinder in which the piston operates. op rating connections between a door and said piston. means tor imparting an upward movement to aid piston and operating connections to open said door. means for storing energy during such upward movement of the piston comprising a coiled spring and a chamber in said cylinder above said piston. means for adn'iitting and temporarily retaining fluid under pressure in said chamber for a sullicient time to enable the pressure fluid thus admitted and retained to assist said coiled spring in actuating said piston on the return (door closing) stroke, said fluid under pressure passing beneath said piston before entering the chamber above said piston.

15. A door operating mechanism having in combination means for applying manual power to open the door, mean constantly acting and of suflicient power to of itself close the door, and means for supplying additional power to assist said constantly acting means, said last named means being supplied before the completion of the opening stroke.

16. In an elevator door operating mechanism, the combination with a door of a set of toggle levers pivotally connected to the door at one end and to a stationary support at the other, means acting through said toggle levers for opening the door, means comprising a piston connecting With said toggle levers and a spring disposed so as to exert a force upon said piston tending to move the latter in the direction to close the door, said spring having sufiicient power to effect such closing of the door through the instrumentality of said piston and connecting toggle levers, and means for supplying additional power to assist said spring comprising a fluid pressure connection for admitting fluid under pressure to the door closing side of said piston while said piston is moving in the direction to open the door.

Signed at New York city, N. Y., this 19th day of June, 1923.

WVILLIAM B. CROlVELL. 

